Wednesday, 6 January 2016

Announcing DSD Master v1.2.2

This version corrects a flaw with the previous update when creating Hybrid-DSD files.

Version 1.2.2 is a free update for all existing DSD Master users.

Tuesday, 22 December 2015

Announcing DSD Master v1.2.1

DSD Master v1.2.1 is released.  This is a minor update of v1.2 and includes a couple of bug fixes.
  • Fixes a bug where no no output file was produced when specifying a manual Gain setting.
  • Corrects the progress bar to show time spent writing metadata.

Monday, 7 December 2015

Announcing DSD Master v1.2

We announce the release of version 1.2 of DSD Master.  This update provides some minor performance enhancements and also some stability improvements.  V1.2 is a free upgrade for existing DSD Master users.

Thursday, 7 May 2015

Announcing DSD Master v1.1

After a successful first year we are finally announcing our first update to DSD Master.  This update is mainly a spin out of minor bug fixes, but it also includes a major under-the-hood revision of our DSP engine in preparation for some significant enhancements of capability.

The new DSP engine delivers a significant increase in processing speed, yet with a dramatically reduced physical and virtual memory footprint.  Conversions are even more accurate, and we now use what we term "True Analog" normalization, which ensures that our PCM conversions do not encode for implied "inter-sample peaks" which can be a problem in certain circumstances.  Improved queueing logic allows large conversion batches to be managed more efficiently.

We have eliminated a stupid bug that requires new installations of DSD Master to make a PCM conversion before it can create Hybrid-DSD files, and another bug which leaks files handles and prevents large conversion batches to be run.

Finally, there are some minor cosmetic changes, including the ability to select files for conversion via a "File | Open" dialog on the menu bar.

Thursday, 1 May 2014

DSD Master, and Importing into iTunes

Many audiophiles who use iTunes as their principal music library tend to be individuals who accumulate large music collections. I myself have close to 30,000 tracks. However, I have heard from many BitPerfect users who have as many as 75,000 tracks. A friend of mine has close to 7,000 CDs arrayed across many, many storage shelves, so I can see how that would be possible.

When you have a collection that big, your best solution is to store the music off-line, on an external HD or, better still, a NAS (which is my preferred solution). When it comes to iTunes, this naturally raises the issues of whether or not to allow iTunes to copy your music into your Media Folder upon import, and whether or not to allow it to Organize your music fielder for you. Both of those features are implemented as check boxes in the Advanced tab of iTunes’ Preferences menu. When you start off using iTunes, and you have a small music collection, having iTunes do all the heavy lifting for you can be a bonus, but eventually you reach the point where you are no longer happy with the way iTunes does things and you want to do it yourself. Most BitPerfect users - myself included - fall into this camp. There is no way I’m letting iTunes organize my music for me

However, if you are happy letting iTunes do all the organizing of your Music Library, then there are some things you need to be aware of when using DSD Master.

DSD Master has a neat feature which allows you to automatically import the files it has created into iTunes. However, if you have iTunes set to “Copy files to iTunes Media Folder when adding to the library”, you will need to look out for a couple of things. First, if you set DSD Master’s output directory to be, for example, a folder on your Desktop, then after the files have all been created and successfully imported into iTunes, you will have duplicates of each - one in the folder on your Desktop and the other somewhere in your iTunes Media folder. You won’t need both copies, so you can safely delete the original one on your Desktop. Of course, if you specify the iTunes Media folder as DSD Master’s output directory this problem goes away completely.

An interesting thing happens if you choose to check iTunes setting “Keep iTunes Media Folder Organized”. This does two things. First, it organizes the music files in the iTunes Media folder into folders by Artist, and sub-folders by Album. This information is gleaned from the metadata in the music files during the import process. Secondly, it is also liable to rename the files according to some internal Apple logic. At this point, I don’t know what that logic is, but if you are creating Hybrid-DSD files, these will be renamed from “filename.DSDh.m4a” to “filename.m4a”. There will be no loss in functionality, but if you were hoping to rely on the “.DSDh.” to identify the Hybrid-DSD files in future, then this useful feature will be lost.

Thanks to BitPerfect User Eric Tan for drawing my attention to this.

Monday, 10 March 2014

Minor Bug in DSD Master

It appears that there is a minor bug in DSD Master.  We will issue an update with a fix pretty soon, but in the meantime the workaround is very simple.

If the first thing you try to do with DSD Master is make a Hybrid-DSD file it will fail.  Instead, it is necessary to first make an Apple Lossless file.  You just have to do it once.  That is all that is needed to make the bug go away forever.  After you have done that you can create Hybrid-DSD files.

Sunday, 17 November 2013


BitPerfect Sound Inc. has been interested in DSD playback since early 2012.  Initially, our interest was in learning about the format, and understanding how it works and how the various playback solutions functioned.  We wanted to understand how Sigma-Delta Modulators work (these are the complex devices which create a DSD data stream), and to understand why - also how, and even if - DSD sounded different to high-resolution PCM.  We acquired some software, co-opted some fellow-travellers, and began to experiment with converting PCM to DSD and vice-versa.

One of the first things we discovered was that different software which performed the DSD-to-PCM conversions produced PCM tracks which sounded markedly different.  On one hand, this should not have been a surprise, since we knew that the conversion process is inherently not lossless, but on the other hand you can never be certain whether the differences will actually be audible, given the superb audio specifications claimed for both DSD and high-resolution PCM.  It was therefore a considerable surprise to us that the differences were not only audible, but that the magnitude of the differences was so great.  This was concerning to us, since even the poorest performing (at least based on our subjective assessment) software is being used to produce commercial products for purchase and download.

We were interested to see if we could understand the factors which can result in adverse sonic characteristics.  It turned out that, yes, we could identify those factors, and having done so we used those results to define an algorithm and methodology which we believed could produce significantly improved results.  After substantial testing we came to the conclusion that our results are audibly superior to all of the the alternatives currently on the market.  We have now reached the point where we know of no way in which to significantly improve upon these results.  These advances are now available to you as DSD Master.

[Note:  It is interesting that the opposite is not the case.  Converting PCM to DSD is a technical challenge which is exponentially more complicated both to understand and to execute.  We have a lot more work ahead of us before we can hope to launch a PCM-to-DSD converter for which we can make similar claims.]

So what kind of technologies lie behind DSD Master?  DSD-to-PCM conversion is at its core a two-step process.  First, the DSD datastream is passed through a low-pass filter.  Second, the output of the filter is passed through a sample rate converter.  Optimizing these processes is, at least in part, a matter of trading off several factors: (i) the time taken to perform the calculations; (ii) the amount of memory needed to store the intermediate calculation results; and (iii) the minimum CPU specification demanded; against the performance of the filter and converter.  The design of filter is crucial here as the filter's characteristics will impact - among other things - the frequency and phase responses of the converter (and also the impulse response, which is a convolution of the frequency and phase responses).  Each of these characteristics is very important, and you cannot achieve ideal behavior from all three simultaneously.  A critical aspect of filter design comes from your choice of which compromises are acceptable and which are not.  Additionally, if you expect a lot from your filter, you must be aware of the numerical precision with which both the hardware and software will execute the calculations, and assure yourself that it will be able to deliver the accuracy you require at the output.  Finally, you can easily throw away all the benefits of a well-executed filter by adopting a sample rate converter of less than comparable quality.  Where compromise is called for, DSD Master has chosen wherever possible to sacrifice process speed for performance.

As we developed this product, we were thinking that a significant motivation for BitPerfect users was to enable them to make the best possible versions of their DSD tracks so they could load them into iTunes and play them through BitPerfect.  But this was not too persuasive an argument, since if customers had gone to the trouble and expense of purchasing DSD music, then they wanted to play it natively, and would probably instead use a different player to play them.  This was a doubly frustrating realization for us, since BitPerfect internally has long been able to play DSD.  The problem has always been that you cannot load DSD files into iTunes.  We realized, however, that we could use DSD Master as the basis for a very elegant solution to this problem - we call this solution our "Hybrid-DSD" file.  You can read more about that here.  These "Hybrid-DSD" files can be loaded into iTunes, will automatically play PCM music if iTunes is used without BitPerfect, and, if BitPerfect is in use, will play DSD if the DAC supports it and PCM otherwise.  This, finally, is the solution we have been looking for for some time.